Sciencemadness Discussion Board

Sulfuric acid on skin contact

Polesch - 6-10-2012 at 08:15

"Discuss topics pertaining to mad science (...)" So I guess this is the perfect place for this discussion.

About 5 months ago, as I was pouring some concentrated (96%) sulfuric acid over into a small round bottom flask, approximately 10-12 drops fell on my left thigh, just above the knee. The cotton fabric had no chance, and the acid dissolved through in a split second, I didn't realize the spill before a large hole appeared in my pants. I ran out and poured around 10 liters of cold water over my thigh and foot - I never felt a slight bit of pain or discomfort from the acid itself. In the next two weeks the skin was sore and dry, I regularly cleaned it with an antiseptic just in case. The soreness and dryness went away, but the spot itself looks exactly the same now 5 months later - just like a bruise.

I assume the strong hygroscopic nature of concentrated sulfuric acid pulled water out from deep into the skin, killing the cells and stopping blood flow. Is it just dead blood cells embedded in fat tissue that I'm seeing?

More important, will it ever heal? Go away? Fade? Any similar experiences out there?

Bot0nist - 6-10-2012 at 08:43

Cold, concentrated sulfuric acid has been on my hands many times with no harm. Just rinsed away quickly. No pain, no discoloration. Maybe a bit of dryness.

Perhaps the action on the cotton heated it up a bit, or it was on you for too long. Dont move acid over yourself and maybe a lab apron could help in the future.

If the spot looks necrose or dead seek medical attention. 5 months is pretty long, even for discoloration. It would have to be deep I would assume. Maybe consult a dermotologist.

plante1999 - 6-10-2012 at 09:23

I have a tiny triangle spot on one of my finger from nitric/sulfuric acid mix. I got this injury in 2009 and it is still like it was one month after it happened. The wound is a 3 mm equilateral triangle with PVC white coloration. To the touch it feel like normal skin. It doesn't hurt. I don't know why it doesn't goes away...

Bot0nist - 6-10-2012 at 09:33

Mmmm, nitro-skin. Pretty sure Vulture has a thread on this in Whimsy.

A concentrated nitrating bath once spilled across my nitrile gloved hands and ate through immediatly. While at the sink washing off, the gloves I stripped off and tossed down began to hiss and pop and catch fire. The RFNA + sulfuric mix left a yellow stain on my hands, but no lasting discoloration.

How long were the mixed acids in contact with your flesh? Ever get ~25% hydrogen peroxide on your flesh. That is an unforgetable feeling, and leaves very unique bright white blisters.

PPE and proper technique is key to safety, it seems.

[Edited on 6-10-2012 by Bot0nist]

Endimion17 - 6-10-2012 at 09:34

Mixture of concentrated acid and the products of cotton disintegrating in it might be more corrosive to the skin than just the acid.
If there's enough time, it's always better to first quickly dab (not wipe) the acid from the skin, and then apply lots of cold water, but if the time is critical, water should be used first.

plante1999 - 6-10-2012 at 09:49

Quote: Originally posted by Bot0nist  

How long were the mixed acids in contact with your flesh? Ever get ~25% hydrogen peroxide on your flesh. That is an unforgetable feeling, and leaves very unique bright white blisters.

PPE and proper technique is key to safety, it seems.

[Edited on 6-10-2012 by Bot0nist]


Maybe 10h since I did the reaction in at 6h00 in the morning and at 16h I eaten a sandwich and remarked the wound and washed it but it didn't do much. Since the time I take lot more precaution! If it wasn't the case I would be probably dead by now. I learned quite fast lab safety with some permanent mark... I am not able to smell certain odor, some odor are extremely irritating for me and I smell them from long distance( vinegar for example, the smell is so irritating you can't even imagine, hydrogen chloride is baby stuff). No I never had a hydrogen peroxide wound since peroxide is only 3% here and when I made my 30% I took large amount of precaution.

Hexavalent - 8-10-2012 at 12:18

I've never had laboratory acids on my skin, a combination of good lab technique and luck I guess.

Possibly the worst chemical injury I've had is a a cough that lasted a few days as a result of sulfur dioxide, and another from hydrogen chloride.

zed - 9-10-2012 at 11:38

Skin is pretty resilient. Still, Concentrated H2SO4 has burned many a lovely young Muslim girls face off. Rejected suitors of the psychopathic inclination, throw acid in the girls faces as a means of revenge.

Since poor folks in Pakistan and India, don't have running water in their houses, and may not even have a pitcher of water in the house, injuries are often horrific.

We've all had a bit of H2SO4 on our hands, the trick is to get it off quickly....Before it has time to work its magic. Hot, concentrated, H2SO4? All bets are off. It has a BP of about 200C, which by itself can burn you to the bone.

hissingnoise - 9-10-2012 at 12:03

Quote:
It has a BP of about 200C, which by itself can burn you to the bone.

Actually, 'concentrated' sulphuric acid is its 98.3% azeotrope, boiling @~337°C.
Pure, 100% H<sub>2</sub>SO<sub>4</sub> boils @ ~228°C


violet sin - 10-10-2012 at 12:59

I JUST had the pleasure of a refresher course in sulfuric spill. yayyy. was trying to remove plastic wrapper from jug( ACE drain cleaner). but for some idiotic reason decided to do it after I had already opened it. don't ask I don't know why I paused to do this in the middle of pouring operation... any how opening the basement door with acid on hands not so easy. was on for less than 10sec would say much more like7 sec, ate my shirt and blistered my for arm in a nifty pink splatter pattern complete with drippy trails as it ran down my arm. fells nice and WARM when you wash it off with water....
just glad I am not blind now. wasn't wearing safety goggles. ( I know, I know, I know buying face sheild in 5 min for clean up fun) time to revamp all safety protocol. I moved past the few simple projects to funner more diverse and colorful salts n reactions, but my lab had not grown more safe in pace. I have been around chemistry for a long time and it is what I consider an enlightened hobby. learning and fun. was my major in college a decade ago, so I know better. this is the worst spill I have ever had to date.
only blisters, no charring or loss of senses. learned again that there is no such thing as a simple/safe procedure with strong chems( with out necessary safety equipment ). I own goggles, gloves, smock, and a scratched face shield( thats why I don't use it often), etc, etc, but got over confident because of familiarity and safe procedures over the years. wasn't apparent till my concentration slipped and I had no safety net in place. concentration and focus is all fine and well, but no one is focused ALL the time. so back up is needed. word to the wise, prepare for the worst or stick to the safe.. I am dialing back experiments till I can increase safety enough. guess its simple stuff for a while, but it's good motivation to improve my habits. wife is kinda pissed too.

8#'s baking soda, check. face shield, check. time to clean up, sure is. noticed I got it on some of my drywall hanging gear and mud finishing tools.... good thing a lot if it is stainless steel. (I hang and finish drywall for a living) kinda funny the nylon didn't take it so well, turned bright pink and ate right thru. tools can be replaced, the ability to use them, not so much so I count myself quite lucky.


[Edited on 10-10-2012 by violet sin]

Eddygp - 14-11-2012 at 13:22

Worst thing I've had is a short cough from hydrogen chloride and some sulphur dioxide fumes...
I guess in a couple of years I'll already have strange bruises like you.

[Edited on 14-11-2012 by Eddygp]

Pyro - 14-11-2012 at 13:29

I have quite a few scars on my hands from many things, a few of them being H2SO4.
I got one on my neck once too!

feacetech - 14-11-2012 at 14:06

Quote: Originally posted by zed  
Skin is pretty resilient. Still, Concentrated H2SO4 has burned many a lovely young Muslim girls face off. Rejected suitors of the psychopathic inclination, throw acid in the girls faces as a means of revenge.

Since poor folks in Pakistan and India, don't have running water in their houses, and may not even have a pitcher of water in the house, injuries are often horrific.

We've all had a bit of H2SO4 on our hands, the trick is to get it off quickly....Before it has time to work its magic. Hot, concentrated, H2SO4? All bets are off. It has a BP of about 200C, which by itself can burn you to the bone.



They most likely use diluted acid like the kind in a car battery

actually car battery H2SO4 is at its most dangerous conc for the skin (excluding olem)

I have had small amounts of conc H2SO4 on my skin and had plenty of time to clean it off, without ill effect

it depends on how sweaty you are

The heat generated form diluting large amounts of conc H2SO4 off you skin is another story and depends on what you do first before washing the acid off

Urzah - 15-11-2012 at 08:42

I do always wear lab coat and gloves when using strong chemicals. However, accidents happens.

A few years ago, I was diluting concentrated sulfuric acid, wearing every protective clothing I can, in a working fumehood. Didn't noticed a drop fell on my shoe. Later in the day, my foot were goin itchy. Didn't bothered. Later in the evening, when undressing, I niticed the hole in my shoe. Then the hole in my sock. Then the big burn on my foot... I had a real burn for few weeks but it stayed marked for a few months.

Never mess with those acids...



[Edited on 15-11-2012 by Urzah]